Reduced energy waveform for energizing solenoid actuator in fuel injector valve
AssigneeCaterpillar Inc.
InventorsAndrew O. Marrack, Daniel Reese Puckett, Mitchell B. Juchems
Life of this patent
Estimating the term…
Abstract
Operating an engine system and fuel system includes energizing a solenoid actuator for a spill valve in a fuel injector in a first engine cycle via a standard waveform to inject a shot of fuel. Operating an engine system and fuel system further includes determining suitability for reduced energy operating of the fuel system, and energizing the solenoid actuator via a reduced energy waveform based on the determining suitability so as to inject one or more shots of fuel in a second engine cycle. The operating methodology and control logic can extend an engine speed range for multi-shot fuel injection in an engine.
Claims14
A method of operating a fuel system for an engine comprising:
- energizing a solenoid actuator for a valve of a fuel injector in a first engine cycle of an engine via a standard waveform;
- injecting a shot of fuel in the first engine cycle based on the energizing a solenoid actuator via a standard waveform;
- determining suitability for reduced energy operating of the fuel system;
- energizing the solenoid actuator in a second engine cycle of the engine via a reduced energy waveform based on the determining suitability for reduced energy operating of the fuel system;
- injecting a shot of fuel in the second engine cycle based on the energizing a solenoid actuator via a reduced energy waveform;
- and
- the standard waveform is defined in part by a first power supply parameter indicative of a first power supply used in producing the standard waveform, and the reduced energy waveform is defined in part by a second power supply parameter different from the first power supply parameter and used in producing the reduced energy waveform.
A method of operating a fuel system for an engine comprising:
- energizing a solenoid actuator for a valve of a fuel injector in a first engine cycle of an engine via a standard waveform;
- injecting a shot of fuel in the first engine cycle based on the energizing a solenoid actuator via a standard waveform;
- determining suitability for reduced energy operating of the fuel system;
- energizing the solenoid actuator in a second engine cycle of the engine via a reduced energy waveform based on the determining suitability for reduced energy operating of the fuel system;
- and
- injecting a shot of fuel in the second engine cycle based on the energizing a solenoid actuator via a reduced energy waveform;
- wherein each of the standard waveform and the reduced energy waveform is defined by a pull-in current having a greater amplitude, a keep-in current, and a hold-in current having a lesser amplitude;
- and
- wherein the pull-in current and the keep-in current of the standard waveform are produced by a higher voltage power supply, and the keep-in current of the reduced energy waveform is produced by a lower voltage power supply.
A fuel system for an engine comprising:
- a fueling control unit including an energizing waveform controller structured to:
- energize a solenoid actuator via a standard waveform to actuate a valve in a fuel injector in a first engine cycle;
- determine suitability for reduced energy operating of the fuel system;
- energize the solenoid actuator via a reduced energy waveform to actuate the valve in a second engine cycle based on the determined suitability for reduced energy operating of the fuel injector;
- and
- switch from a higher voltage power supply to a lower voltage power supply during the energizing of the solenoid actuator in a second engine cycle;
- wherein each of the standard waveform and the reduced energy waveform is defined by a pull-in current having a greater amplitude, a keep-in current, and a hold-in current having a lesser amplitude;
- and
- wherein the pull-in current and the keep-in current of the standard waveform are produced by the higher voltage power supply, and the keep-in current of the reduced energy waveform is produced by the lower voltage power supply.
Dependencies are inferred from the claim text.